Over the last 50 years, obesity has been increasing at an alarming rate and is now recognized by leading government health authorities, such as the Centers for Disease Control (CDC) and National Institutes of Health (NIH), as a disease. In the United States alone, obesity affects more than 60 million individuals and is considered the second leading cause of preventable death. Worldwide, approximately 1.6 billion adults are overweight, and it is estimated that obesity affects at least 400 million adults.
Obesity is caused by a wide range of factors including genetics, metabolic disorders, physical and psychological issues, lifestyle, and poor nutrition. Millions of obese and overweight individuals first turn to diet, fitness and medication to lose weight; however, these efforts alone are often not enough to keep weight at a level that is optimal for good health. Surgery is another increasingly viable alternative for those with a Body Mass Index (BMI) of greater than 40. In fact, the number of bariatric surgeries in the United States is projected to reach approximately 400,000 annually by 2010.
Examples of surgical methods and devices used to treat obesity include the The LAP-BAND® (Allergan, Inc., Irvine, Calif.) gastric band and the LAP-BAND AP® (Allergan, Inc., Irvine, Calif.). However, surgery might not be an option for every obese individual; for certain patients, non-surgical therapies or minimal-surgery options are more effective or appropriate.
For example, intragastric balloons may be utilized as non-surgical or minimal-surgery means for treating obesity. One such inflatable intragastric balloon is described in U.S. Pat. No. 5,084,061 and is commercially available as the BioEnterics Intragastric Balloon System (sold under the BIB® System). These devices are designed to provide therapy for moderately obese individuals who need to shed pounds in preparation for surgery, or as part of a dietary or behavioral modification program.
The BIB® System, for example, comprises a silicone elastomer intragastric balloon that is inserted into the stomach and filled with fluid. Conventionally, the balloons are placed in the stomach in an empty or deflated state and thereafter filled (fully or partially) with a suitable fluid. The balloon occupies space in the stomach, thereby leaving less room available for food and creating a feeling of satiety for the patient. Clinical results with these devices show that for many obese patients, the intragastric balloons significantly help to control appetite and accomplish weight loss.
Placement of such balloons is temporary, and such balloons are typically removed after about six months. One means of removing the balloon is to deflate it by puncturing the balloon, and either aspirating the contents of the balloon or allowing the fluid to pass into the patient's stomach. Alternatively, if the balloon is left in place beyond its designed lifetime, the acids present in a patient's stomach may erode the balloon to the point where it self-deflates. When this occurs, the deflated balloon may pass naturally through the patient's digestive system and be expelled through the bowel. For instance, McGhan, U.S. Pat. No. 6,733,512, describes a self-deflating intragastric balloon that includes a biodegradable inflation valve. After a certain residence time in the stomach, the valve starts to leak and eventually the balloon deflates and passes though the patient's digestive tract.
Despite the advances in the design of intragastric balloons, there remains a need for improved transoral obesity treatment devices.